Have you thought about why the Sunny 16 Rule is always accurate with full sun?
If so, please offer an explanation:).
Why does the Sunny 16 Rule work?
Have you thought about why the Sunny 16 Rule is always accurate with full sun?
If so, please offer an explanation:).
No I have not thought about sunny 16 for many years and I cannot remember why it works. I am looking forward to the explanation, and I guess I will have to go back to start using it again
Come on - anyone else ?
I wouldn't have the foggiest, but I'ld like to know why.
According to Wikipedia, the sunny 16 rule is based on incident light. As you know, a reading from an incident light meter only considers the light and not the scene/subject matter. I don't know why the sunny 16 rule works (perhaps I should take a look at my old exposure book) but I'm guessing this little piece of information could be showing where our thinking should be heading.
My understanding of sunnyf16 comes from the film days. K64 at f16 at 60th sec SS = proper exposure in full sun. Then you changed the aperture and SS to give the proper exp from that point (K64 at f5.6 at 500th sec SS = proper exp in full sun). If it's cloudy or not full sun yet, you would have to compensate. Of course the best exposures were made with this formula with the sun at your back and the subjects important parts lit. The camera meters were calibrated to this sensitivity. I have used this with the digitals and it works, probably because the new meters and sensors are calibrated to these sensitivities also, at least with the Nikons I use.
The sunny 16 rule work because the maximum intensity of the sun is a known factor.
Our sun only gets so bright and no brighter.
The sun's maximum intensity comes from a cloudless sky, between the first and last 2.5-3 hours of the day.
I know without metering - on a sunny 16 day using ISO 400, I will expose a middle tone subject correctly @ 1/1600 F8 or a white subject correctly @ 1/2000 F8
Hi James,
I have just noticed this thread, and because I am currently making a big effort to learn Exposure Theory, I was going to answer: it was because the light level is a constant. But it seems I got here too late!
However I am interested in your choice of 1/2000, f/8, ISO400 for exposing the whites, as Arthur M states that whites should be exposed at one stop of underexposure relative to the correct middle tone exposure. (Is your shutter speed choice because you capture your whites brighter, eg. if you were spot metering the whites would you add 2 stops compensation, rather than 1 1/3 ? I have just tried to work it out on a piece of paper but converting incident light compensation into reflected light compensation always gives me a headache! It's much easier with a camera in my hands and a suitable subject.)
Please let me know,
Julian.
Photoshop Cafe have a DVD entitled - "Perfect Exposure for Digital Photographers" - all about using the zone system with Digital Photography - It is very good, easy to understand and whilst it does concentrate on spot metering - the theory behind it is solid and easy to understand.
One of the best things I have seen on Exposure theory!
[QUOTE=Julian Mole;572855]
However I am interested in your choice of 1/2000, f/8, ISO400 for exposing the whites [quote]
If I may jump in...
With ISO = 400, the exposure value of f16 1/400 (the sunny 16 rule) = f11 1/1000s = f8 1/2000s. The only difference is the depth of field resulted, or the burriness of the subject matter if it's in motion.
Are you sure you've read it correctly, that it's not for when the white has a larger, darker background behind it?as Arthur M states that whites should be exposed at one stop of underexposure relative to the correct middle tone exposure.
You could try this experiment: photo a white piece of paper. Let the entire paper cover the entire field of view. Shoot a photo using the exposure setting your camera tells you. Shoot another one with one stop under (-1 EV), then two stops under (-2 EV), one stop over (+1 EV), and two stops over (+2 EV). Take a look at the photos and see which one looks white and close to the white paper you've just photographed. My bet is that the ones with the recommended settings and the two under-exposed would look grey, or more grey than the two over-exposed.
Just in case, the recommended settings give you Zone V grey, the under-exposed give you Zone IV and Zone III. The over-exposed give you Zone VI and Zone VII.
I'd suggest that whatever suggested + or - EV compensations you've learned anywhere, you should try them and adjust them based on the performance of your camera. The recommended settings are what they are: recommendations.
Back to the experts.
Hi Lance,
Thank you for the recommendation I shall look into it once I have the basics sorted - I have read a little bit about the Zone system but am yet to fully understand it.
Julian.
Hi Desmond,
Thank you for your reply. The quote about placing the whites at one stop of underexposure (relevant to the correct middle tone exposure) is definitely in reference to Incident Light and the Sunny 16 rule (I believe it's sometimes called the Sunny 22 rule) as mentioned in Arthur's ABP I book in the chapter about Exposure Theory.
Anyway, refering back to my question to James Shadle, after a good night's sleep I realised this morning that I had been a bit thick! What James has done is place the whites at a 1/3 stop of underexposure (relative to the correct middle tone exposure) and this is indeed the same as spot metering the white itself and adding +2 stops.
(I checked out the theory a few weekends ago with some large convective clouds and found that if I followed Arthur's advice and spot metered the brightest part of the cloud and added 1 1/3 stops compensation this worked out the same as spot metering a middle gray cloud and subtracting 1 stop, which he explains is becasue they are effectively the same exposure just reached in a different way. However I did find that with my Canon 40D this meant that the brightest whites were rendered more of a light gray, so I found myself instead spot metering the brightest part and adding 2 stops, which just so happens to work out the same as spot metering a middle tone cloud and subtracting 1/3 stop!
Phew! Hope that makes sense!)
I shall also give your exercise a go at some point, although I couldn't get out today because of horrible rainy weather.
Julian.
PS. Here is a photo of one the clouds I used to better understand how the Incident/ Reflective theory works: http://farm5.static.flickr.com/4108/...4c33d535_o.jpg
Last edited by Julian Mole; 09-29-2010 at 06:19 PM.
You're welcome Julian.Originally Posted by Julian Mole
From pane 4 of this thread:Anyway, refering back to my question to James Shadle, after a good night's sleep I realised this morning that I had been a bit thick! What James has done is place the whites at a 1/3 stop of underexposure (relative to the correct middle tone exposure) and this is indeed the same as spot metering the white itself and adding +2 stops....
http://www.birdphotographers.net/for...arkIV-Metering
Among other things, I particularly agree with Artie on the followings:
"Folks make getting the right exposure with digital much too complicated..."
"...Different digital camera bodies from the same or from different manufacturers will almost always require different amounts of EXP Compensation..."
"There is no need to come up with a "perfect exposure" with digital..."
I personally would change the first quote above to "folks make getting the right exposure much too complicated"
Good luck !
Desmond
Last edited by Desmond Chan; 09-30-2010 at 12:06 AM.
What James has done is place the whites at a 1/3 stop of underexposure (relative to the correct middle tone exposure)
You are correct Sir.
Trying to get your head around the difference between metering light falling and light reflected can cause head aches.
You compensate for tonality with the Sunny 16 the same way you would an incident light meter(light falling) - you just don't need the meter:D.
Thanks Desmond for those Artie quotes - although I was already aware of them as they were made in a thread I started! :-)
It may seem that I am making things too complicated for myself, but all I am just trying to do is gain a fuller understanding of exposure theory, which will help me become a better photographer, one capable of capturing those actions shots which don't allow time to guess at an exposure and then correct it after viewing the histogram.
Regards,
Julian.
Thanks James.
Posting Permissions
